Digesting apparatus



(No Model.) A. SELKIRK.

DIGIESYTING APPARATUS.

No. 487,783. Patented Dec 13,1892} Z'Zzzessas; & i M ad ams virus 00..P'Hm'ou'ruu, wAsmmrmy. o. c;

UNITED STATES PATENT Curios,

ALEXANDER SELKIRK, OF ALBANY, ASSIGNOR, BY MESNE ASSIGNMENTS, TO ROBERTIVl-IlTEl-IILIQ AND DANIEL \VARING, OF NEVVBURG, NE\V YORK.

DIGESTING APPARATUS.

SPECIFICATION forming part of Letters Patent No. 487,783, dated December13, 1892.

Application filed May 31,1889. Serial No. 312,749. (No model.) Patentedin Germany August 15, 1888, No. 46,940: in England August 16, 1888,110.11,848; in France August 16, 1888, No. 192,466; in Belgium August16,1888,No.82,939; in Norway August 20, 1888, No. 1.0% in Sweden August21, 1888, No. 1,900, and in Austria-Hungary February 20, 1889, No.

33,742 and No. 54,310.

To all whom it may concern.-

Be it known that I, ALEXANDER SELKIRK, a citizen of the United States,residing at Albany, in the county of Albany and State of New York, haveinvented certain new and useful Improvements in Digesting Apparatus,which apparatus may be used in the performance of a process fordisintegrating vegetable substances, (for which I have obtained patentsin the following countries, viz: Great Britain, No. 11,818, dated August16, 1888; Austria-Hungary, No. 33,7 12 and No. 54,310, dated February20, 1889; Germany, No. 46,940, dated August 15, 1888; France, No.192,166, :5 dated August 16, 1888; Belgium, No. 82,939, dated August 16,1888; Norway, No. 1,043, dated August 20, 1888, and Sweden, No. 1,900,dated August 21, 1888,) of which the follow ing is a specification.

My invention relates to a digesting apparatus for treating vegetablesubstances with cooking liquors for dissolving the soluble portions ofthe same; and it consists of the devices and elements and combinationsof devices and elements hereinafter particularly described, andspecifically set forth in the claims.

In the accompanying drawing, forming a part of this specification, thefigure illustrates a sectional elevation of the digesting apparatusembodying the essential elements and devices in this invention.

In the drawing, A represents a digestingvessel, which is preferably madeof steel, 5 though it can be made of iron or other suitable material,and has its parts riveted together and made both steam and liquor tight,so as to sustain an internal pressure of from sixty to one hundred andfifty pounds per square inch. This digesting-vessel contains within itthe digesting-chamber A, which occupies nearly the entire length of thisvessel and has for its bottom the perforated diaphragm a, which is shownin the drawing to be inclined. This perforated diaphragm or bottom ofthe digesting-chamber A separates the latter from the liquor-chamber Awhich occupies the lower end portion of the digesting-vessel.

B is a blow-off pipe or opening at the bottom of the digesting-chamberand is provided with a blow-off cook or valve B, through which thecooked product of the vessel will be discharged. I

O is an opening orpassage-way leading from the outside of thedigesting-vessel to the digesting-chamber within, and through thisopening the material to be cooked can be introduced. This opening isclosed by a suitable cover 0', secured by bolts or other de- 69 vices ina steam-tight manner. In the upper end of this digesting-vessel isarranged a perforated plate or diaphragm a, which limits the extensionof the digesting-chamber and produces above the same the liquor-chamberA which chamber is shown to be concentric to the opening or passage-wayO. The drawin g shows the wall inclosing the passage-way O andseparating it from the liquor-chamber A to be perforated; yet in somecases the perfo- 7o rations in this circular wall can be omitted. Aperforated plate can be employed to close the lower end of thepassage-way C, if preferred. At about midway between the two ends of thedigesting-vessel is the annular chamber D, which chamber is formedbetween the shell of the vessel and the perforated wall d. This chamberthus formed is concentric to the digesting-chamber at the middle portionofits has a covering next to the digesting-chamber, made of finewire-cloth suitably secured to the metal of the perforated wall.

E is a pump situated at any suitable place and preferably convenientlynear the digesting-vessel and has a capacity suitable for dischargingabout three hundred gallons (more or less) of liquor per minute and isoperated by any suitable power. (Not shown.)

This pump communicates with the digesting-vessel by means of a suitablesystem of pipes and valves connected, respectively, with the inlet andoutlet of the pump and with the digesting-vessel at three points, sothat the draft of the pump will draw the cooking solution or liquor fromone of the liquorchambersanddischargethesameintosomeone or two of theliquor-chambers at the will of the operator. Although the system ofpipes employed for effecting these results can be varied, yet I preferto use, substantially, the arrangement and combinations of the severalpipes, their connections, and cooks or Valves shown in the drawing to beemployed between the pump and the digesting-vessel, whereby I am enabledto control and variously change at will the circulation of liquor fromone direction to another and from a single direction or circulation to adual circulation in opposite directions through the digesting-chamber.In this preferred system or arrangement of pipes between the pump E andthe digesting-vessel A is the main draftpipe F, leading from the annularliquor-chamber D to the inlet of the pump, as in direction of arrow 1.In the course of this pipe F there is a valve or cock e, which can beopened and closed at will to a greater or less extent. Through this pipethe cooking solution or liquor will be drawn from the liquorchamber D tothe pump when valve c is opened.

G is abranch outlet-pipe connected with the outlet of pumpE and withpipe H and branch pipe I. Pipe H leads from branch g of the branch pipeG to the liquor-chamber A and is provided with valve or cook 7L. Branchpipe I is connected with the branch 9 of the branch pipe G, and one ofthe branches of this branch pipe I, as branch pipe 1', connects withpipe J, which communicates with the lower liquor-chamber A In the courseof this pipe J is a valveor cock j, which controls the volume of liquorpassing through said pipe. The branch 1" of branch pipe I conmeets withpipe I, which communicates with pipe F by branch f, and a cock f isprovided in the course of the pipe I for controlling the circulation ofliquor through the same. The horizontal limb of pipe F is connected withthe horizontal limb of pipe J by means of suitable branches or pipes K,and in the course of this pipe K there is placed a valve 70. Betweenpipes H and F and preferably between their horizontal limbs is pipe L,which is connected with said pipes H and F by suitable branches, as Hand F. In the course of this pipe L is placed the cock or valve 1. Withthis above-described system of pipes and valves between the pump and thedigesting-vessel there can be produced at will a variety of circulationsof the cooking solution or liquor into and through thedigesting-chamber. WVhen valve e of pipe F and valve h of pipe H andvalve j of pipe J are opened and valvef of pipe I and valve 713 of pipeK and valve Z of pipe L are closed and the pump is operated, the liquoror solution will be drawn from the annular chamber D in direction ofarrow 1 into the pump and be discharged into the branch outlet-pipe Gand thence in two directions into the digesting-vessel, in which oneportion of the solution or liquor will be discharged in direction ofarrow 2 through pipe II into the upper liquor-chamber A from whence theliquoror solution will have passage downwardlyin direction of arrow 3and through the upperhalf portion of the digesting-chamber, whileanother portion of the liquor, drawn through pipe F fromliquor-circulating chamber D, will be made to pass from branchoutlet-pipe G in direction of arrow 4 and through pipe J into the lowerliquor-chamber A and from thence through the perforated bottom ordiaphragm a into the lower half portion of the digestingchamber tocirculate upwardly through the material therein in direction of arrows5. The operation of the pump being continued, the liquor or solutionwill be continuously drawn from the annular liquor-chamber D into thepump through pipe F and be continuously discharged by the pump throughthe pipes H and J into the respective liquor-chambers A and A and fromthence into the charge being treated to circulate indirections,respectively, as indicated by arrows 3 and 5, and toward the middle ofthe length of the digesting-chamber, where the solution or liquor of thetwo currents will mingle and be drawn together by the force of the pumpthrough the perforated wall d into the annular liquor-chamber D to berepeatedly returned into the digest- .ing-chamber in two streams to becirculated as above described. By partially closing the valve h in pipeH and leaving valvejor pipe J fully opened a large portion of thesolution or liquor drawn from the annular chamber D through pipe F willbe discharged into the lower end of the digesting-chamber to circulateupwardly in direction of arrow 5 to be returned to the annularliquor-chamber D, while a smaller volume of liquor will be made to passthrough pipes H and be discharged into the upper portion of thedigesting-chamber to circulate downwardly and in direction of arrow 3;but when valve h is fully opened and valve j of pipe J is partly closeda greater volume of the solution or liquor will be discharged throughpipe H into the upper liquor-chamber A than will be through pipe J intothe lower liquor-chamberA and thereby cause a greater volume of theliquor or solution to circulate downwardly through the upper halfportion of the charge within the digesting-chamber than will becirculated upwardly through the lower half portion of the same. Whenvalve h is fully closed, all the liquor drawn through pipe F will bedischarged into the lowerliquor-chamberA and be wholly made to circulatethrough the lower half portion of the charge being treated, and whenvalve j is wholly closed and valve h is opened all the liquor drawnthrough pipe F will be discharged through pipe H into the upperliquor-chamber A and from thence pass downwardly in small streamsthrough the upper half portion of the charge'within thedigesting-chamber. When valve 70 of pipe K is opened and cock or valve71, of pipe II is also opened and cook or valves e,f,j, and l areclosed, the pump will draw the liquor from the lower end of thedigesting-vessel through parts of pipes J and F and discharge the samethrough pipe lI into the upper liquor-chamber A so that the circulationof the liquor willbe downwardly through the entire length of the chargewithin the digesting-vessel and into thelower liquor-chamber A to beagain drawn by the pump through pipe J and returned into the upper endof the digestingwessel in a continuous manner as long as the pump isoperated and the valves are turned as above described. When thedigesting-vessel is filled with water or liquor up to the mouth of pipeH and cook or valve Z of pipe L and cock or valve j of pipe J are openedand the other valves or cocks are closed, the pump when operated willdraw the liquor from the upper liquor-chamber A through the horizontallimb of pipe H and the pipe L and. thehorizontal limb of pipe F anddischarge the same through branch 9 of branch pipe G andpipe J into thelower liquor-chamber A from whence the liquor will be circulatedupwardly through the entire length of the digesting-chamber, to bereturned to the upper liquor-chamber A and, with the respective cocks orvalves, opened and closed as above described, and, the pump operatingcontinuously, the water or liquor, by the force of pump E, will becontinuously circulated upwardly through the mass of material within thedigesting-chamber.

I have shown only one pump employed for drawing the liquor from theannular chamber D and discharging the same into the opposite ends of thedigesting-vessel 5 yet, if desired, two pumps can be employed as theequivalent of the single pump shown for drawing the liquor from the saidannular chamber and discharging the same into the opposite ends of thedigesting-vessel, and in such a case each of the pumps will be connectedby a suitable separate draft-pipe with the said annular chamber and byseparate dischargepipeswith the opposite ends of the digestingvessel, sothat when one of the pumps is drawing the liquor from the annularchamber D and discharging the same into the upper end of thedigesting-vessel the other pump will be drawing liquorfrom thesamechamberand discharging it into the lower end of said vessel.

M is alive-steam-supply pipe leading from any suitable steam-generator(not shown) and connecting with steam-pipes M, from which ternalperforated wall (Z of said annular are extended branches M and M,communicating, respectively, with the upper and lower ends of thedigesting-vessel, and preferably with the liquor chambers A and A. Inthe course of steam-pipe- M is placed a valve m. In the course of pipe Mis valve m These valves are under the control of the operator, who willregulate the volume of steam admitted to the digesting-vessel as may berequired during the progress of the treatment of the material to bereduced. Acheck-valve is preferably placed in the course of each of thepipes M and M By the employment with the digesting-ms sel of the annularliquor-chamber D, with its internal perforated wall cl, and the pump E,with pipes F, H, and J, as above described, I am enabled to produce acontinuous dual circulation of the cooking solution or liquor throughthe material being treated within the digesting-chamber. In this dualcirculation the liquor will be drawn continuously from thedigesting-chamber into the annular liquorchamber D and from thence becontinuously drawn and discharged by the pump through pipes F, H, and Jinto the respective chambers A and A at the opposite ends of the vesseland from thence circulate in directions toward each other, as indirections of arrows 3 and 5, with a portion passing upwardly throughthe interstices between the particles of material in the lower halfportion of the digesting-chamber and downwardly through the intersticesbetween the particles composing the upper half portion of the same. Theupward circulation of the liquor in direction of arrow 5 through thelower half of the mass of material of thecharge, together with thebuoyant force of the liquor, operates to counteract the tendency of thecharge to settle down and prevents the packing of the material on theperforated bottom of the digesting-chamber. At the same time the draftof the pump through pipe F on the liquor in the annular liquor-chamber Doperates to prevent the middle portion of the mass of material in thedigesting-chamber from packing together, so that the more internalportions of the charge will be kept loosened, and thereby afford to theliquor'a free circulation through the same without any substantialpacking of the material horizontally and hard against theinliquor-chamber. Withthisannularliquor-chamber D midway between theends of the digesting-vessel and with a draft-pipe F drawing from thisannular liquor-chamber I am en abled to employ with a full charge ofmaterial a comparatively-small volume of water or liquor, and bycirculating this small volume of liquor with the dual circulation, asabove described, I am enabled to supply the material being treated witha suitable amount of the cooking-liquor for completely dissolving thesoluble portions of the material in all parts of the digestingvessel.

By the employment of the perforated diaphragm or devices in the upperend portion of thedigesting-vessel for the passage of the liquor innumerous small steams through the same, with liquor extending up to ashort distance above the mouth of draft-pipe F (as to liquor-line N) andwith the pipes F, II, and J between the pump E and the respectiveliqnor-chambers A A and D, the lower half portion composing the chargewill be completely submerged in the cooking liquor, while the upper halfportion of the charge will be kept constantly saturated (withoutsubmergence) by the volume of liquor being discharged into chamber A andsprayed down on the upper surface of the material to percolatedownwardly through the interstices between the particles composing theupper half of the charge and circulate in contact with the same, so thatevery particle in the upper half portion of the charge will have such aliberal supply of liquor as may be necessary to contribute to the rapidand uniform cooking or dissolving of the soluble portions of thematerial. By means of the live-steam pipes M M M M, connecting thedigestive vessel with a steam-generator, (not shown,) live steam can beintroduced at will into the digesting-vessel in greater or less volume,as may be required from time to time in the progress of the cooking ofthe charge, to sufficiently heat the water or liquor which is beingconstantly circulated with this dual circulation through the mass ofmaterial within the digestingvessel.

I have described herein merely the use of steam-pipes for supplying livesteam directly to the digester and heating the cooking liquor; but othermeans may be employed for the purpose in connection with the hereindescribed and claimed system of liquor-circulatin g devices, andalthough some means for the purpose is necessary to the conduct of theoperation no claim is made herein to combinations of the devices forcirculating the liquor with means for heating the same, as suchcoinbinations form the subjects of separate applications, Serial No.301,877, filed March 5,1889, and Serial No. 312,750, filed May 31, 1889,the claims in this case being limited to the means for effecting thespecified dual circulation of the liquor irrespective of the means whichmay be employed for heating it. The process of digesting the materialwhich is carried out in the apparatus herein described and claimed, alsoforms the subject of a separate application, Serial No. 282,0l2, filedAugust 4, 1889, and is not claimed herein.

Ilaving described my invention, what I claim, and desire to secure byLetters Patent, 1s'

1. In a digesting apparatus, the combination, with a digesting-vesseland a 'pump, of an annular perforated wall supported within the saidvessel between the end portions thereof and forming with the wall ofsaid digestingvessel an annular liquor-chamber, a draft-pipe leadingfrom said annular liquor-chamber to the inletof the pump, anddiseharge-pipesleading from the outlet of the pump into thedigesting-vessel through the respective end portions thereof,substantially as and for the purposes set forth.

2. In a digesting apparatus, the combination, with a digesting-vesselhaving a liquorchamber in its lower end portion separated fromdigesting-chamber by a perforated diaphragm and an annularliquor-chamber between the end portions of said digestingchamber andseparated therefrom by a perforated annular wall suitably supported fromthe solid wall of the digesting-vessel, of a pump, a draft-pipe leadingfrom said annular liquor-chamber to the pump, and two discharge-pipesleading, respectively, from the pump into the opposite end portions ofthe digesting-vessel, one of them into the liquorchamber below thedigesting-chamber, substantially as and for the purposes set forth.

3. In a digesting apparatus, the combination, with the digesting-vesselcontaining upper and lower liquor-chambers separated from each other bythe digesting-chamber and the interposed perforated diaphragms a a andan annular liquor-chamber communicating with the digesting-chamberthrough the perforated annular wall (Z at about midway between the endsof the said chamber, of a pump, draftpipe F, and dischargepipes Hand J,provided with suitable valves, substantially as and for thepurposes setforth.

4. In a digesting apparatus, the combination, with the digesting-vesselhaving its digestingchamber separated from a liquorchamber below by theperforated diaphragm a and an annular liquor-chamber about midwaybetween the ends of said digesting-vessel and communicating with saiddigesting-chamber through the perforated annular wall (I, of a pump,pipes F, J', K, I, I, and II, and valves 6,), h,j, and 70, substantiallyas and for the purposes set forth.

ALEXANDER SELKIRK.

Witnesses:

WILLIAM R. BROWN, CHARLES SELKIRK.

